Have you ever run across the word viandas? It is generally translated "root vegetables" or "tubers," referring to potatoes, sweet potatoes, yuca and other similar vegetables that grow underground.
In Argentina, however, the meaning is completely different.
The word vianda in Argentina refers to a prepared meal, a lunch or dinner box that a child or adult takes with them to school or work. The general idea is that a person takes their lunch to eat healthier than if fast food was purchased and to also save some money in the process.
Look here for more Argentina Spanish Slang Word articles.